Many people wonder about dairy’s role when feeling unwell. This common question stems from traditional beliefs and personal experiences, prompting a look at popular perceptions versus scientific evidence.
The Mucus Myth
A widespread belief suggests that consuming dairy products increases mucus production or thickens phlegm, especially during a cold or respiratory illness. This idea has been around for centuries, with some historical texts, like those from the 12th-century physician Moses Maimonides, contributing to the notion that dairy causes “a stuffing in the head.” The influential “Dr. Spock’s Baby and Child Care” book also helped popularize this claim in the 20th century.
This perception often stems from the physical sensation milk creates in the mouth and throat. Milk’s creamy texture can temporarily coat the mouth and mix with saliva, leading to a feeling of thicker saliva or a coated throat. This feeling can be mistaken for increased mucus, even though it does not reflect a change in the actual amount or consistency of respiratory secretions.
What the Science Says
Despite the persistent popular belief, scientific research generally does not support the claim that dairy products increase mucus production in the respiratory system. Numerous studies have investigated this connection and consistently found no significant association between dairy intake and increased mucus, congestion, or other respiratory symptoms.
For instance, a study involving volunteers intentionally infected with the common cold virus found no link between milk consumption and higher levels of nasal secretions or more severe congestion. Interestingly, some research indicates that people who already believe dairy causes mucus tend to report more respiratory symptoms after consuming it, even when their measured mucus levels are no different from those who do not hold this belief.
Dairy and Other Sickness Symptoms
While the link between dairy and mucus production is largely a myth, dairy can affect individuals differently when they are sick due to other factors, primarily digestive sensitivity. Many people experience lactose intolerance, a condition where the body does not produce enough lactase, the enzyme needed to break down lactose, the sugar found in milk. When undigested lactose reaches the large intestine, it can lead to uncomfortable symptoms.
These symptoms commonly include bloating, gas, stomach cramps, nausea, vomiting, and diarrhea. Illnesses or intestinal infections can temporarily reduce lactase production, worsening lactose intolerance even in those who normally digest dairy well. Additionally, the fat in some dairy products can be difficult for a compromised digestive system to process, potentially increasing nausea or discomfort.
Making Dairy Choices When Sick
When deciding whether to consume dairy during illness, listening to your body’s specific reactions is important. If dairy products cause digestive upset, such as bloating, gas, or diarrhea, it may be beneficial to temporarily reduce or avoid them. This helps prevent additional discomfort while your body recovers.
Opting for easily digestible dairy options is a practical approach. Lactose-free or lactose-reduced products are alternatives for those with lactose intolerance. Probiotic-rich yogurts can also support gut health, especially if you are experiencing diarrhea. Always choose pasteurized dairy products, as raw milk poses serious health risks, particularly when your immune system is weakened.